This is an excerpt from the second verse of a 13-verse, 65-line Latin poem of the 4th century concerning the life of
Christ, Quando noctis medium. It is Hymn 29, pp. 41-2 from Franz Mone's
Hymni latini medii aevi, Volume 1 of 3, Hymni ad Deum et Angelos. (Freiburg:
Sumptibus Herder, 1853), taken from a Stuttgart MS. of
the 14th century that reflected the belief that the Messiah was born
on the stroke of midnight.

One translation is "When in silence and in shade" by
John Mason Neale, in the Hymnal Noted, Part II, Hymn 50, Quando
noctis medium, pages 101-102 (1854), melody
from the Spanish Graduals. His translation of the first two verses is:

1. When in silence and in shade
Earth, at midnight, had been laid,
Working out the Fatherís plan,
In the Virginís womb made Man,
God His earthly life began.

2. By each mouth His praise be showed
For the new gift now bestowed;
From on high came down the dew,
From the earth the floweret grew,
Health in mortals to renew.

It is also found in The Hymnary, Hymn 10
(1872); the tune was "Hymnary No. 10" by Henry Thomas Smart.

For the complete seven verses by John Mason Neale,
see: When In
Silence And In Shade. Seven verses in English and Latin are reproduced in
John Freeman Young, ed., Great Hymns, Hymn 19, Quando noctis medium
("When in Silence and in Shade"), pp. 26-27. It was noted that "three stanzas of
this Hymn are omitted."

A writer in Notes and Queries gave another
translation, from an unidentified source, of these three lines:

"The dew descends from above,
and out of the earth springs a flower,
the perfume of which is our cure."